This is particularly notable because nobody really reads terms of service. When they change, they're either ignored, or misunderstood to the point that people think posting a disclaimer on their Facebook walls will prevent the company from using their data.

The reaction highlights how much people use and care about Instagram, but it also points out a huge trend in people's attitudes that will affect corporate strategy for years to come.

People are increasingly aware that what makes many digital businesses valuable is the personal data and content they upload. And they've seen this trend over and over again when businesses go public or get bought out and attempt to monetize the data.

Increasingly—and Instagram's PR crisis will only accelerate this—people are on the lookout for companies that change their terms of service or become increasingly intrusive in the way they go about it.

An acquisition of a favorite company has become a cue to watch it closely.

In addition to figuring out how to make money, companies will have to be strategic about how they disclose what they're doing to account for the reaction to those efforts. Had Facebook and Instagram, for example, consulted its users about the language or content of their new terms of service, they might have avoided the whole thing.